Number of words (with or without meaning) that can be formed from all letters of word "LETTER&q

English

Gujarati

Hindi

6.Permutation and Combination

medium

The number of words (with or without meaning) that can be formed from all the letters of the word $"LETTER"$ in which vowels never come together is

A

$80$

B

$100$

C

$120$

D

$60$

(JEE MAIN-2020)

Solution

LETTER

vowels $= EE ,$ consonant $= LTTR$

$- L _{-} T _{-} T _{-} R _{-}$

$\frac{4 !}{2 !} \times{ }^{5} C _{2} \times \frac{2 !}{2 !}=12 \times 10=120$

Standard 11

Mathematics

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